Methods and systems for heating and mixing fluids

ABSTRACT

A fluid heating system includes a tank assembly having an interior surface bounding a chamber, the tank assembly including a sidewall and a lid. A collapsible bag is removably disposed within the chamber of the tank assembly, the collapsible bag bounding a compartment adapted to hold a fluid. A boiler can be used for pumping heated fluid through the wall of the tank assembly for heating the fluid within the collapsible bag. An impeller is disposed within the compartment of the collapsible bag. An elongated drive shaft is removably coupled with the impeller such that rotation of the drive shaft facilitates rotation of the impeller within the compartment of the collapsible bag. A drive motor assembly is coupled with the drive shaft, the drive motor assembly being adapted to rotate the drive shaft when the lid is in an open or closed position.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates to systems and methods for heating andmixing fluids which can be used for inactivating cells ormicroorganisms.

2. The Relevant Technology

The biopharmaceutical industry uses a broad range of mixing systems fora variety of processes such as in the preparation of media and buffersand in the growing or processing of cells and microorganisms. Manyconventional mixing systems, including bioreactors, comprise a rigidtank that can be sealed closed. A drive shaft with impeller is rotatablydisposed within the tank. The impeller functions to suspend and mix thecomponents.

In many cases, great care must be taken to sterilize and maintain thesterility of the mixing system so that the culture or other product doesnot become contaminated. Accordingly, between the production ofdifferent batches, the mixing tank, mixer, and all other reusablecomponents that contact the processed material must be carefully cleanedto avoid any cross contamination. The cleaning of the structuralcomponents is labor intensive, time consuming, and costly. For example,the cleaning can require the use of chemical cleaners such as sodiumhydroxide and may require steam sterilization as well. The use ofchemical cleaners has the additional challenge of being relativelydangerous, and cleaning agents can be difficult and/or expensive todispose of once used.

Once processing step commonly used with biological fluids containing aculture is to heat the fluid to a defined temperature to kill orinactivate the cells or microorganisms therein. This has historicallybeen accomplished by heating the fluid within a stainless steel tank.Such processing, however, again requires the cleaning and sterilizationof the tank between different batches.

Accordingly, what is needed in the art are system that permit controlledand uniform heating of a fluid that does not require washing orsterilization between batches and that minimizes any potential forbreach in sterility.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present invention will now be discussed withreference to the appended drawings. It is appreciated that thesedrawings depict only typical embodiments of the invention and aretherefore not to be considered limiting of its scope.

FIG. 1 is perspective view of a fluid heating system incorporatingfeatures of the present invention;

FIG. 2 is a cross sectional side view of the tank assembly of the fluidheating system shown in FIG. 1;

FIG. 3 is a bottom perspective view of the tank assembly shown in FIG.2;

FIG. 4 is a perspective view of the tank assembly shown in FIG. 1 withthe lid in a closed position;

FIG. 5 is a cross sectional side view of the fluid heating system shownin FIG. 1;

FIG. 6 is a front side plan view of the container assembly shown in FIG.1 in a collapsed position;

FIG. 7 is a back side plan view of a container assembly shown in FIG. 6in a collapsed position;

FIG. 8 is an exploded perspective view of a temperature port assembly ofthe container assembly shown in FIG. 6 with related parts;

FIG. 9 is a cross sectional side view of the temperature port assemblyshown in FIG. 8;

FIG. 10 is an elevated side view of an impeller assembly and drive shaftused in the fluid heating system;

FIG. 11 is a partially disassembled perspective view of the impellerassembly, drive shaft and drive motor assembly of the fluid heatingsystem;

FIG. 12 is an enlarged view of the rotational assembly and drive motorassembly in a disassembled view state; and

FIG. 13 is an elevated front view of the rotational assembly and drivemotor assembly coupled together.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to systems and methods for heating fluidsbut can also be used for mixing and/or cooling fluids. The systems cancommonly be used for inactivating cells or microorganism in a biologicalfluid by heating the fluid. For example, the systems can be used forinactivating yeast cells by heating media containing the cells to adefined temperature and then holding the media at the temperature for adefined time. The systems can be used with other cells or microorganismand can be used for heating and/or mixing other biological ornon-biological fluids for other purposes such as sterilization or fluidprocessing.

The inventive systems are designed so that a majority of the systemcomponents that contact the material being processed can be disposed ofafter each use. As a result, the inventive systems substantiallyeliminate the burden of cleaning and sterilization required byconventional stainless steel mixing systems. This feature also ensuresthat sterility can be consistently maintained during repeated processingof multiple batches. In view of the foregoing, and the fact that theinventive systems are easily scalable, relatively low cost, and easilyoperated, the inventive systems can be used in a variety of industrialand research facilities that previously outsourced such processing.

Depicted in FIG. 1 is one embodiment of an inventive fluid heatingsystem 10 incorporating features of the present invention. In general,fluid heating system 10 comprises a tank assembly 12, a containerassembly 16 that is disposed within and supported by tank assembly 12,and a drive shaft 18 (FIG. 2) that extends between tank assembly 12 andcontainer assembly 16. Container assembly 16 houses the fluid orsolution that is heated and can also be mixed and/or cooled. The variouscomponents of fluid heating system 10 will now be discussed in greaterdetail.

Continuing with FIG. 1, tank assembly 12 comprises a tank body 102having a lid 104 hingedly coupled thereto. Tank body 102 comprises asubstantially cylindrical sidewall 106 having an interior surface 108that extends between an upper end 110 and an opposing lower end 112. Asdepicted in FIG. 2, tank body 102 also includes a floor 114 located atlower end 112 with a drain opening 116 extending therethrough. Interiorsurface 108 of sidewall 106 and floor 114 bound a chamber 118. Asdiscussed below, chamber 118 is configured to receive container assembly16 so that container assembly 16 is supported therein. A substantiallyC-shaped lip 120 is formed at upper end 110 of sidewall 106 andpartially bounds an access opening 122 to chamber 118. A pair of spacedapart slots 124A and B are recessed on lip 120 and, as will be discussedbelow in greater detail, provide channels through which fluid lines canpass out of chamber 118 when lid 104 is closed.

In general, tank body 102 has a front face 126 and an opposing back face128. As best shown in FIG. 1, an enlarged notch 130 is formed on frontface 126 at upper end 110 and extends through sidewall 106 and lip 120.Disposed within notch 130 so as to communicate with chamber 118 is adrive motor assembly 132. As will be discussed below in greater detail,drive motor assembly 132 is used to rotate drive shaft 18 (FIG. 2) whichin turn mixes the fluid within container assembly 16. Although notrequired, drive motor assembly 132 is typically fitted so that notch 130is sealed closed. A generally U-shaped flange 134 having a top surface136 extends between opposing sides of notch 130 along an inside face ofdrive motor assembly 132. Top surface 136 at opposing ends of flange 134is flush with lip 120 so that lip 120 and flange 134 combine to formsealing surface 137 that bounds access opening 122 of chamber 118.

As shown in FIG. 3, formed on back face 128 of tank body 102 is a hinge138 that connects lid 104 to tank body 102. Hinge 138 enables lid 104 tobe manually moved between an open position as shown in FIG. 1 and aclosed position as shown in FIG. 4. A handle 142, shown in thisembodiment as having a U-shaped configuration, is formed on lid 104 toassist in movement of lid 104 between the two positions. Continuing withFIG. 3, a piston 140 has a first end hingedly coupled with a lid portion141 of hinge 138 and an opposing second end hingedly coupled with tankbody 102. Piston 140 assists in smooth and controlled movement of lid104 so that lid 104 does not unintentionally slam shut. Lid 104 has anotch 144 formed on a front face thereof opposite hinge 138. Notch 144is sized to receive drive motor assembly 132 when lid 104 is in theclosed position (FIG. 4). Returning to FIG. 1, lid 104 has an insideface 148 having a gasket 150 extending along a perimeter edge thereof.When lid 104 is in the closed position, gasket 150 sites on top ofsealing surface 138 so that drain opening 116 to chamber 118 issubstantially sealed closed. It is noted that when lid 104 is closed,slots 124A and B (FIG. 2) will still be open to chamber 118 which can bea source of heat loss. Such heat loss, however, is negligible. Ifdesired, inserts can be placed within slots 124A and B to seal them offwhen not in use. In some embodiments, slots 124A and B can beeliminated.

As shown in FIG. 4, tank assembly 12 also includes a locking assembly152 that helps to ensure a tight and secure sealed engagement betweenlid 104 and tank body 102. In the embodiment depicted, locking assembly152 includes a catch 154 formed on and radially outwardly projecting outfrom lid 104. Catch 154 has a slot 155 (FIG. 1) formed on an end facethereof. In turn, a fastener 156 is mounted on tank body 102 below catch154. Fastener 156 includes a threaded bolt 158 having a first endhingedly mounted to tank body 102 and an opposing second end having ahandle 160 threaded thereon. When lid 104 is in the closed position,fastener 156 is rotated so that bolt 158 is received within slot 155 ofcatch 154. Handle 160 can then be selectively rotated to advance alongbolt 158. In so doing, handle 160 biases against catch 154 and clampslid 104 to tank body 102. If desired, two or more locking assemblies 152can be used. In alternative embodiments, it is appreciated that thedepicted locking assembly 152 can be replaced with any number ofconventional locking systems such as latches, clamps, fasteners, screws,elastic cords, or any other structure that can temporarily secure lid104 to tank body 102. In yet other embodiments, locking assembly 152 canbe eliminated.

Although tank body 102 is shown as having a substantially cylindricalconfiguration, in alternative embodiments tank body 102 can have anydesired shape capable of at least partially bounding a chamber. Forexample, sidewall 106 need not be cylindrical but can have a variety ofother transverse, cross sectional configurations such as polygonal,elliptical, or irregular. Furthermore, it is appreciated that tank body102 can be scaled to any desired size. For example, it is envisionedthat chamber 118 of tank body 102 can be sized to hold a maximum volumeof fluid in a range between about 50 liters to about 2,500 liters withabout 75 liters to about 1,000 liters being common and about 75 litersto about 300 liters being more common. Other sizes can also be used.Tank body 102 and lid 104 are typically made of metal, such as stainlesssteel, but can also be made of other materials capable of withstandingthe applied loads and temperatures of the present invention.

In one embodiment of the present invention means are provided forcontrolling the temperature of the fluid that is contained withincontainer assembly 16 when container assembly 16 is disposed withinchamber 118 of tank assembly 12. By way of example and not bylimitation, tank body 102 and lid 104 can both be jacketed so as tobound one or more fluid channels through which heated or cooled fluidcan pass. In turn, heat from the heated fluid flowing through tankassembly 12 radiates to the fluid within container assembly 16 forheating the fluid therein. Alternatively, chilled fluid flowing throughtank assembly 12 draws heat from the fluid within container assembly 16for cooling the fluid therein. For example, as shown in FIG. 2, sidewall106 comprises an inside wall 162 and an outside wall 164 that bound afluid channel 166 therebetween; floor 114 comprises an inside wall 168and an outside wall 170 that bound a fluid channel 172 therebetween; andlid 104 comprises an inside wall 174 and an outside wall 176 that bounda fluid channel 178 therebetween. If desired an insulation layer 179 canbe positioned between each outside wall 164, 170, and 176 and thecorresponding fluid channel.

Turning to FIG. 3, outside wall 176 of lid 104 has an inlet port 180 andan outlet port 182 formed thereon and communicating with fluid channel178 (FIG. 2). A hose coupling 181 is coupled with inlet port 180. Hosecoupling 181 is designed to couple with a fluid line that extends from athermal control unit (TCU) 197 or some other source for generating orproviding a heated or cooled fluid so that the fluid can be pumped intofluid channel 178 at a desired temperature and flow rate. The fluid canbe water, propylene glycol, or other types of fluids commonly used inthis type of heating or cooling. In one embodiment, the TCU 197 cancomprise a boiler 198 fluid coupled with a pump 199 which delivers thefluid to house coupling 181. A chiller and other components can also beused.

Outside wall 162 of sidewall 106 has an inlet port 184 and an outletport 186 formed thereon and communicating with fluid channel 166 (FIG.2). A fluid line 188 extends from outlet port 182 on lid 104 to inletport 184 of sidewall 106 so that after the heated fluid passes throughfluid channel 178 in lid 104 it can then pass through fluid channel 166in sidewall 162. In turn, outside wall 170 of floor 114 has an inletport 190 and an outlet port 192 formed thereon and communicating withfluid channel 172 (FIG. 2). A fluid line 194 extends from outlet port186 on sidewall 106 to inlet port 190 of floor 114 so that after theheated fluid passes through fluid channel 166 in sidewall 162 it canthen pass through fluid channel 172 in floor 114.

Finally, a hose coupling 196 is coupled with outlet port 192 of floor114 so that a fluid line can be coupled therewith and extend back to TCU197 where the fluid is then heated or cooled back to the desiredtemperature before repeating the cycle. The fluid flow system can thusbe a close loop, recirculating system. It is appreciated that partitionsor other structures can be formed within fluid channels 166, 172, and178 to optimize fluid flow throughout so that tank body 102 and lid 104apply a substantially uniform and continuous heat or cooling around allsides of container assembly 16 when container assembly 16 is disposedwithin tank assembly 12.

In alternative embodiments, it is appreciated that the heated or cooledfluid can enter through hose coupling 190 on floor 114 and then exit outthrough hose coupling 181 on lid 104. In still other embodiments,separate recirculating systems can be coupled with each of lid 104,sidewall 106 and/or floor 114. In contrast to using a heated liquidfluid, heated gas or steam can be used. Alternatively, the means forcontrolling the temperature can comprise electrical heating elementsplaced on the exterior surfaces of inside walls 162, 168, and 174. Otherconventional heating or cooling systems can also be used. The means forcontrolling the temperature can be used to heat the fluid withincontainer assembly 16 to a temperature in a range between about 30° C.to about 130° C. with about 50° C. to about 70° C. being more common.Other temperatures can also be used.

As also shown in FIG. 2, tank assembly 12 also includes a support 200secured to interior surface 108 of sidewall 106 at upper end 110.Support 200 includes a flange 202 attached to and projecting fromsidewall 106 and a substantially C-shaped retainer 204 disposed at theend thereof. Retainer 204 includes a stem 206 and a flange 208 radiallyoutwardly projecting therefrom, both stem 206 and a flange 208 having asubstantially C-shaped configuration. As will be discussed below ingreater detail, support 200 is used for supporting a portion ofcontainer assembly 16 and for supporting a temperature probe 210therein.

As shown in FIG. 1, tank assembly 12 is typically mounted on a platform212. If desired, one or more load cells can be incorporated intoplatform 212 so that the quantity of fluid delivered to containerassembly 12 when disposed within tank assembly 12 can be accuratelymeasured. FIG. 1 also shows an electrical controller 214. Controller 214can be used for measuring and controlling operational parameters such asthe heat and flow rate of fluid through the fluid channels, as discussedabove, tracking the time and temperature that the fluid within containerassembly 12 is heated, measuring the weight of fluid entering containerassembly 12 and controlling mixing of the fluid within containerassembly 12 as will be discussed below in greater detail.

Turning to FIG. 5, container assembly 16 comprises a container 18 havinga side 20 that extends from an upper end 22 to an opposing lower end 24.Upper end 22 terminates at a top 23 while lower end 24 terminates at abottom 25. Container 18 also has an interior surface 26 that bounds acompartment 28. Compartment 28 is configured to hold a fluid. In theembodiment depicted, container 18 comprises a flexible bag that iscomprised of a flexible, water impermeable material such as alow-density polyethylene or other polymeric sheets having a thickness ina range between about 0.1 mm to about 5 mm with about 0.2 mm to about 2mm being more common. Other thicknesses can also be used. The materialcan be comprised of a single ply material or can comprise two or morelayers which are either sealed together or separated to form a doublewall container. Where the layers are sealed together, the material cancomprise a laminated or extruded material. The laminated materialcomprises two or more separately formed layers that are subsequentlysecured together by an adhesive.

The extruded material comprises a single integral sheet that comprisestwo or more layers of different materials that can be separated by acontact layer. All of the layers are simultaneously co-extruded. Oneexample of an extruded material that can be used in the presentinvention is the HyQ CX3-9 film available from HyClone Laboratories,Inc. out of Logan, Utah. The HyQ CX3-9 film is a three-layer, 9 mil castfilm produced in a cGMP facility. The outer layer is a polyesterelastomer coextruded with an ultra-low density polyethylene productcontact layer. Another example of an extruded material that can be usedin the present invention is the HyQ CX5-14 cast film also available fromHyClone Laboratories, Inc. The HyQ CX5-14 cast film comprises apolyester elastomer outer layer, an ultra-low density polyethylenecontact layer, and an EVOH barrier layer disposed therebetween. In stillanother example, a multi-web film produced from three independent websof blown film can be used. The two inner webs are each a 4 mil monolayerpolyethylene film (which is referred to by HyClone as the HyQ BM1 film)while the outer barrier web is a 5.5 mil thick 6-layer coextrusion film(which is referred to by HyClone as the HyQ BX6 film).

The material is approved for direct contact with living cells and iscapable of maintaining a solution sterile. In such an embodiment, thematerial can also be sterilizable such as by ionizing radiation.Examples of materials that can be used in different situations aredisclosed in U.S. Pat. No. 6,083,587 which issued on Jul. 4, 2000 andUnited States Patent Publication No. US 2003-0077466 A1, published Apr.24, 2003 which are hereby incorporated by specific reference.

In one embodiment, container 18 comprise a two-dimensional pillow stylebag wherein two sheets of material are placed in overlapping relationand the two sheets are bonded together at their peripheries to form theinternal compartment. Alternatively, a single sheet of material can befolded over and seamed around the periphery to form the internalcompartment. In another embodiment, container 18 can be formed from acontinuous tubular extrusion of polymeric material that is cut to lengthand is seamed closed at the ends.

In still other embodiments, container 18 can comprise athree-dimensional bag that not only has an annular side wall but also atwo dimensional top end wall and a two dimensional bottom end wall.Three dimensional containers comprise a plurality of discrete panels,typically three or more, and more commonly four or six. Each panel issubstantially identical and comprises a portion of the side wall, topend wall, and bottom end wall of the container. Corresponding perimeteredges of each panel are seamed. The seams are typically formed usingmethods known in the art such as heat energies, RF energies, sonics, orother sealing energies.

In alternative embodiments, the panels can be formed in a variety ofdifferent patterns. Further disclosure with regard to one method ofmanufacturing three-dimensional bags is disclosed in United StatesPatent Publication No. US 2002-0131654 A1 that was published Sep. 19,2002 of which the drawings and Detailed Description are herebyincorporated by reference.

Although in the above discussed embodiment container 18 has a flexible,bag-like configuration, in alternative embodiments it is appreciatedthat container 18 can comprise any form of collapsible container orsemi-rigid container. Container 18 can also be transparent or opaque andcan have ultraviolet light inhibitors incorporated therein.

It is appreciated that container 18 can be manufactured to havevirtually any desired size, shape, and configuration. For example,container 18 can be formed having a compartment sized to 10 liters, 30liters, 100 liters, 250 liters, 500 liters, 750 liters, 1,000 liters,1,500 liters, 3,000 liters, 5,000 liters, 10,000 liters or other desiredvolumes and thus can be in a range between any of the above volumes.Although container 18 can be any shape, in one embodiment container 18is specifically configured to be complementary or substantiallycomplementary to chamber 118 of tank body 102, as discussed above.

In any embodiment, however, it is typically desirable that whencontainer 18 is received within the chamber 118, container 18 is atleast generally uniformly supported by tank body 102. Having at leastgeneral uniform support of container 18 by tank body 102 helps topreclude failure of container 18 by hydraulic forces applied tocontainer 18 when filled with fluid.

Depicted in FIG. 6 is a front side view of container assembly 16 withcontainer 18 in a folded or collapsed position. As shown therein,container assembly 16 includes ports 230A and B secured to upper end 22of container 18. Ports 230A and B can be secured by welding or otherconventional techniques and include a passageway extending therethroughthat communicates with compartment 28 (FIG. 5). Coupled with andextending from ports 230A and B are fluid lines 232A and B,respectfully. Fluid lines 232A and B are typically comprised of aflexible hose or tubing. Mounted on the end of fluid line 232A and B areconnectors 234A and B, respectfully. Connectors 234A and B are designedfor forming a fluid coupling with an additional fluid line, container,or other structure. In one embodiment, connectors 234A and B cancomprise aseptic connectors such as the KLEENPAK sterile connectoravailable from the Pall Corporation. Other sterile or non-sterileconnectors can also be used. An envelope 235 is removable positionedover each connector 234A and B to help maintain sterility prior to use.A tube clamp 238 can also be mounted on each fluid line 232A and B forclosing the fluid lines or controlling the flow of gas or liquidtherethrough. Fluid lines 232A and B are commonly used for deliveringliquids, gases or other components into or out of container 18.

Also mounted at upper end 22 of container 18 is a port 240 having a gasline 242, typically in the form of a flexible hose or tube, extendingtherefrom and having a gas filter 244 mounted on the end thereof. Gasfilter 244 typically has a barbed port 246 formed on the end thereof forremovably receiving a gas line that is coupled with a compressor orother gas source. As will be discussed below in more detail, for properpositioning, expansion and filling of container 18, it is helpful toinitially partially fill container 18 with a gas, such as air. The gascan be delivered through port 246 on gas filter 244. Gas filter 244filters the gas so that no contaminates enter container 18. Oncecontainer assembly 16 is properly positioned within tank assembly 12,fluid and other components can be delivered into container 18 throughone of fluid lines 232A or B while the displaced gas exits out throughthe other fluid line 232A or B. A tube clamp 238 can also be positionedon gas line 242 to selectively close off the passage therethrough.

Finally, also mounted at upper end 22 of container 18 is a temperatureport assembly 250. Turning to FIG. 8, temperature port assembly 250comprises a port 252 that is secured to container 18 and a probe adapter254 that is coupled with port 252. Port 252 has a conventional designthat includes a barbed stem 256 having a passage 258 extendingtherethrough and a flange 260 radially outwardly projecting therefrom.Flange 260 is welded or otherwise secured to container 18 so thatpassage 258 communicates with compartment 28 (FIG. 5). Probe adapter 254comprises a flexible sleeve 264 having a first end 266 and an opposingsecond end 268. Encircling and radially outwardly projecting from firstend 266 is a mounting flange 270. Likewise, encircling and radiallyoutwardly projecting from second end 268 is a support flange 272. Atubular stem 274 projects in axial alignment with sleeve 264 from a sideof mounting flange 270 opposite of sleeve 264.

Probe adapter 254 also includes an elongated receiver 276 having a firstend 278 and an opposing second end 280. As shown in FIG. 9, receiver 276includes an elongated body 281 that typically has a substantiallycylindrical configuration and extends between first end 278 and secondend 280. Body 281 has an interior surface 282 that bound a cavity 284.Body 281 is closed except for an opening 286 formed at first end 278. Atubular catch 288 is mounted on and projects from first end 278 of body281 in alignment with opening 286. A flange 289 encircles and radiallyoutwardly projects from body 281 at first end 286.

During assembly, second end 280 of body 281 is passed down through stem274, mounting flange 270, sleeve 264, and supporting flange 272 so thatsecond end 280 projects down below support flange 272. Body is advanceduntil flange 289 rests against stem 274. In this configuration, afriction tight fit is formed between body 281 and stem 274. However,during radiation sterilization of container assembly 16, body 281 andstem 274 can weld together. Otherwise, if desired, an adhesive or otherconventional welding techniques can be used to secure the structurestogether. In yet other embodiments, probe adapter 254 can be formed as asingle unitary member or as other combinations of members securedtogether.

As also shown in FIG. 9, a cavity 290 is also formed between an interiorsurface 291 of sleeve 264 and the exterior surface of receiver 276.During assembly, port 252 is slid into cavity 290, the parts being sizedso that a friction fit is formed therebetween. A tie 292 can then becinched around sleeve 264 so as to ensure a liquid type seal betweensleeve 264 and port 252.

In the assembled configuration, sleeve 264 is inserted within retainer204 (FIG. 2) of tank body 102 so that mounting flange 270 rests onflange 208 of retainer 204. An annular gasket 294 having an opening 295(FIG. 8) extending therethrough, is then positioned on top of mountingflange 270. Finally, a clamp 296 (FIG. 8), such as a tri-clamp, ispositioned around flange 208, mounted flange 270 and gasket 294 so thatwhen clamp 296 is closed and tightened, these structures are securelyheld together. Port 252 and the portion of container 18 secured theretoare thus secured to and supported by retainer 204. An elongatedtemperature probe 210, commonly referred to as an RTD, can be advanceddown into cavity 284 of receiver 276. A collar 298 mounted on probe 210can be threaded onto catch 288 so as to secure temperature probe 210 toreceiver 276.

By inserting temperature probe 210 within receiver 276, temperatureprobe 210 can measure the temperature of the fluid within container 18through the wall of receiver 276. Receiver 276 protects temperatureprobe 210 from directly contacting the fluid within container 18. Assuch, there is no risk of temperature probe 210 contaminating the fluidand temperature probe 210 can be reused without sterilization or othercleaning. Furthermore, temperature probe 210 is rigidly held in positionat a distance spaced apart from sidewall 162. As such, temperaturesprobe 210 give a more accurate reading of the temperature of the fluidthan if it was positioned adjacent to sidewall 162. Temperatures probe210 is also held at a constant location independent of whether fluid isbeing added or removed from container 18.

Returning to FIG. 6, container assembly 16 also comprises a port 308mounted at lower 24 of container 18, a drain line 310 extending fromport 308, and a tube connector 312, such as a sterile connector, mountedat the end of drain line 310. A hose clamp 238 is also mounted on drainline 310 for closing the passage therethrough. Finally, a support plate314 is shown encircling drain line 310 adjacent to port 308. As shown inFIG. 3, drain opening 116 is typically formed oversized so that it iseasy to reach up through drain opening 116 and grab drain line 310 or tootherwise pass drain line 310 down through drain opening 116. Supportplate 314 is simply a plate that is configured to be received withindrain opening 116 after drain line 310 passes therethrough so thatcontainer 18 can be supported thereon. Support plate 314 can have a slot316 extending therethrough and radially extending in from the perimeteredge so that drain line 310 can be removably slid into slot 316.Alternatively, support plate 314 can simply have a central hole throughwhich drain line 310 is passed during the assembly of container assembly16.

If desired, other ports can be mounted on container 18 for use incoupling other probes to container 18. For example, other ports can beused for coupling probes such as pH probes, dissolved oxygen probes, andthe like. Examples of ports and how various probes and lines can becoupled thereto is disclosed in United States Patent Publication No.2006-0270036, published Nov. 30, 2006 and United States PatentPublication No. 2006-0240546, published Oct. 26, 2006, which areincorporated herein by specific reference. Ports can also be used forcoupling container 18 to secondary containers, to condenser systems, andto other desired fittings.

Depicted in FIG. 7 is a back side view of container assembly 16 withcontainer 18 in a folded or collapsed position. As shown therein,container assembly 16 further comprises an impeller assembly 40. Asdepicted in FIG. 10, impeller assembly 40 comprises an elongated tubularconnector 44 having a rotational assembly 48 mounted at one end and animpeller 64 mounted on the opposing end. More specifically, tubularconnector 44 has a first end 46 and an opposing second end 48 with apassage 50 that extends therebetween. In one embodiment, tubularconnector 44 comprises a flexible tube such as a polymeric tube. Inother embodiments, tubular connector 44 can comprise a rigid tube orother tubular structures.

Rotational assembly 48 is mounted to first end 46 of tubular connector44. Rotational assembly 48 comprises an outer casing 50 having anoutwardly projecting flange 52 and a tubular hub 54 rotatably disposedwithin outer casing 50. A bearing assembly can be disposed between outercasing 50 and tubular hub 54 to permit free and easy rotation of hub 54relative to casing 50. Likewise, one or more seals can be formed betweenouter casing 50 and tubular hub 54 so that during use an aseptic sealcan be maintained between outer casing 50 and tubular hub 54 as tubularhub 54 rotates relative to outer casing 50.

Hub 54 has an interior surface 56 that bounds an opening 58 extendingtherethrough. As will be discussed below in greater detail, an engagingportion of interior surface 56 has a polygonal or other non-circulartransverse cross section so that a driver portion of drive shaft 362passing through opening 58 can engage the engaging portion andfacilitate rotation of hub 54 by rotation of drive shaft 362. Hub 54 canalso comprise a tubular stem 60 projecting away from outer casing 50.Hub 54 can couple with first end 44 of tubular connector 42 by stem 60being received within first end 44. A pull tie, clamp, crimp or otherfastener can then be used to further secure stem 60 to tubular connect42 so that a liquid tight seal is formed therebetween. Otherconventional connecting techniques can also be used.

Impeller 64 comprises a central hub 66 having a plurality of fins 68radially outwardly projecting therefrom. It is appreciated that avariety of different numbers and configurations of fins 68 can bemounted on hub 66. Hub 66 has a first end 70 with a blind socket 72formed thereat. Socket 72 typically has a non-circular transverse crosssection, such as polygonal, so that it can engage a driver portion ofdrive shaft 362. Accordingly, as will be discussed below in greaterdetail, when a driver portion is received within socket 72, the driverportion engages with impeller 64 such that rotation of drive shaft 362facilities rotation of impeller 64.

In one embodiment, hub 66 and fins 68 of impeller 64 are molded from apolymeric material. In alternative embodiments, hub and fins 68 can bemade of metal, composite, or a variety of other materials. If desired,an annular insert can be positioned within socket 72 to help reinforcehub 66. For example, the insert can be comprised of metal or othermaterial having a strength property greater than the material from whichhub 66 is comprised.

Impeller 64 can be attached to connector 42 by inserting first end 70 ofhub 66 within connector 42 at second end 46. A pull tie, clamp, crimp,or other type of fastener can then be cinched around second end 46 ofconnector 42 so as to form a liquid tight sealed engagement betweenimpeller 64 and connector 42.

Returning to FIG. 7, rotational assembly 48 is secured to container 18so that tubular connector 42 and impeller 64 extend into or are disposedwithin compartment 28 of container 18 (FIG. 5). Specifically, in thedepicted embodiment container 18 has an opening 74 at upper end 22.Flange 52 of outer casing 50 is sealed around the perimeter edgebounding opening 74 so that hub 54 is aligned with opening 74. Tubularconnector 42 having impeller 64 mounted on the end thereof projects fromhub 54 into compartment 28 of container 18. In this configuration, outercasing 50 is fixed to container 18 but hub 54, and thus also tubularconnector 42 and impeller 64, can freely rotate relative to outer casing50 and container 18. As a result of rotational assembly 48 sealingopening 74, compartment 28 is sealed closed so that it can be used inprocessing sterile fluids.

As depicted in FIG. 10, impeller assembly 40 is used in conjunction withdrive shaft 362. In general drive shaft 362 comprises a head section 364and a shaft section 366 that can be coupled together by threadedconnection or other techniques. Alternatively, draft shaft 362 can beformed as a single piece member or from a plurality of attachablesections. Drive shaft 362 has a first end 368 and an opposing second end370. Formed at first end 368 is a frustoconical engaging portion 372that terminates at a circular plate 374. Notches 376 are formed on theperimeter edge of circular plate 374 and are used for engaging driveshaft 362 with drive motor assembly 132 as will be discussed below.

Formed at second end 370 of drive shaft 362 is a driver portion 378.Driver portion 378 has a non-circular transverse cross section so thatit can facilitate locking engagement within hub 66 of impeller 64. Inthe embodiment depicted, driver portion 378 has a polygonal transversecross section. However, other non-circular shapes can also be used. Adriver portion 380 is also formed along drive shaft 362 toward first end368. Driver portion 380 also has a non-circular transverse cross sectionand is positioned so that it can facilitate locking engagement withinthe interior surface of hub 54 of rotational assembly 48.

During use, as will be discussed below in further detail, drive shaft362 is advanced down through hub 54 of rotational assembly 48, throughtubular connecter 42 and into hub 66 of impeller 64. As a result of theinterlocking engagement of driver portions 378 and 380 with hubs 66 and54, respectively, rotation of drive shaft 362 by a drive motor assemblyfacilitates rotation of hub 54, tubular connecter 42 and impeller 64relative to outer casing 50 of rotational assembly 48. As a result ofthe rotation of impeller 64, fluid within container 18 is mixed.

It is appreciated that impeller assembly 40, drive shaft 362 and thediscrete components thereof can have a variety of differentconfiguration and can be made of a variety of different materials.Alternative embodiments of and further disclosure with respect toimpeller assembly 40, drive shaft 362, and the components thereof aredisclosed in U.S. patent application Ser. No. 12/697,771 filed Feb. 1,2010 which is incorporated herein in its entirety by specific reference.

As previously discussed with regard to FIG. 1, tank assembly 12comprises drive motor assembly 132 mounted to sidewall 106. Drive motorassembly 132 is used in conjunction with drive shaft 362 (FIG. 10) andcan be used for mixing and/or suspending a culture, solution, or otherfluids within container 18 (FIG. 2). Turning to FIG. 11, drive motorassembly 132 comprises a housing 304 having a top surface 306 and anopposing bottom surface 308. An opening 310 extends through housing 304from top surface 306 to bottom surface 308. A tubular motor mount 312 isrotatably secured within opening 310 of housing 304. Upstanding frommotor mount 312 is a locking pin 316. A drive motor 314 is mounted tohousing 304 and engages with motor mount 312 so as to facilitate selectrotation of motor mount 312 relative to housing 304. Drive shaft 362 isconfigured to pass through motor mount 312 so that engaging portion 372of drive shaft 362 is retained within motor mount 312 and locking pin316 of motor mount 312 is received within notch 376 of drive shaft 362.As a result, rotation of motor mount 312 by drive motor 314 facilitatesrotation of drive shaft 362. Further discussion of drive motor assembly132 and how it engages with drive shaft 362 and alternative designs ofdrive motor assembly 132 are provided in U.S. patent application Ser.No. 12/697,771 which was previously incorporated herein by specificreference.

To facilitate operation, rotational assembly 48 is coupled with drivemotor assembly 132. Specifically, as depicted in FIG. 12, housing 304 ofdrive motor assembly 132 has an open access 384 that is recessed on afront face 386 so as to communicate with opening 310 extending throughhousing 304. Access 384 is in part bounded by a substantially C-shapedfirst side wall 388 that extends up from bottom surface 308, aconcentrically disposed substantially C-shaped second side wall 390disposed above first side wall 388 and having a diameter larger thanfirst side wall 388, and a substantially C-shaped shoulder 392 extendingbetween side walls 388 and 390. As shown in FIG. 5, a door 394 ishingedly mounted to housing 304 and selectively closes the opening toaccess 384 from front face 386. Returning to FIG. 12, door 394 issecured in a closed position by a latch 396. Positioned on first sidewall 388 is a section 398 of a resilient and/or elastomeric materialsuch as silicone. Other sections 398 of similar materials can also bepositioned on first side wall 388 or the interior surface of door 394.

As depicted in FIG. 13, to facilitate attachment of rotational assembly48 to housing 304, with door 394 rotated to an open position, rotationalassembly 48 is horizontally slid into access 384 from front face 386 ofhousing 304 so that a support flange 400 radially outwardly extendingfrom an upper end of rotational assembly 48 rests on shoulder 392 ofaccess 384. Rotational assembly 48 is advanced into access 384 so thatthe passage extending through hub 54 of rotational assembly 48 alignswith the passage extending through motor mount 312 (FIG. 11). In thisposition, door 394 (FIG. 5) is moved to the closed position and securedin the closed position by latch 396. As door 394 is closed, casing 50 ofrotational assembly 48 is biased against the one or more sections 398(FIG. 12) of resilient material so as to clamp rotational assembly 48within access 384 and thereby prevent unwanted rotational movement ofcasing 50 relative to housing 304 of drive motor assembly 132.

Once rotational assembly 48 is secured to drive motor assembly 132,drive shaft 362 (FIG. 10) can be advanced down through drive motorassembly 132 and into impeller assembly 40 so as to engage impeller 64.Once drive shaft 362 is properly positioned, drive motor assembly 132can activated causing drive shaft 362 to rotate impeller 64 and therebymix or suspend the fluid within container 18.

On embodiment of the present invention includes means for mixing thefluid within container 18. One example of such means comprises impellerassembly 40, draft shaft 362 and drive motor assembly 132. Inalternative embodiments of the means for mixing, impeller assembly 40can be replaced with a drive shaft that extends through a dynamic sealon container 18 and has an impeller mounted on the end thereof withincontainer 18. In yet other embodiments, the means for mixing cancomprise a stir bar, impeller or other form of mixer disposed withincontainer 18 and a magnetic mixer disposed outside of container 18 thatcan rotate the mixer within container 18 through the use of a magneticforce. Other conventional mixers can also be used.

One typical example of how the inventive fluid heating system 10 can beused will now be provided. Initially, container assembly 16 isfabricated at a plant so that it is collapsed and sterilized as acomplete assembly. Either just prior to or after placement of containerassembly 16 within compartment 28 of tank assembly 12, containerassembly 16 is partially filled with a gas through gas filter 244 (FIG.6). By so doing, container assembly 16 expands enabling it to be easilypositioned within and coupled to tank assembly 12. Specifically, asshown in FIG. 5, drain line 310 is passed out through drain opening 116in floor 114 and support plate 314 is fitted within drain opening 116;temperature port assembly 215 is coupled with retainer 204 of tankassembly 12 and rotational assembly 48 of container assembly 16 iscoupled with drive motor assembly 132 of tank assembly 12 each haspreviously discussed. At different stages, more gas can be injected intocontainer assembly 16 to ensure proper placement and coupling ofcontainer assembly 16 and to avoid any potential risk of kinkingcontainer 18 as it is filled with liquid.

Once container assembly 16 is properly positioned, fluid line 232A iscoupled with a fluid source while fluid line 232B is coupled with a gasoutlet line. These couplings are made aseptically so as to ensure nobreach and sterility. The desired fluid is then dispensed into container18 through fluid line 232A while the displace gas is passed out throughfluid line 232B. As desired, the fluid and components thereof can bedelivered in different stages. For example, container assembly 16 caninitially be substantially filled with media followed by delivering aculture of cells or microorganisms. During this fluid filling and gasevacuation process, fluid lines 232A and 232B can pass out of tankassembly 12 through slots 124A and B on lip 120. This ensures that iflid 104 is closed, that the fluid lines are not damaged. At some stage,temperature probe 210 is secured within probe adaptor 254 as discussedabove. The electrical wires extending from temperature probe 210 canlikewise pass out through a slot 320 formed on lip 120 of tank assembly12 as shown in FIG. 1, so as to avoid any damage thereto when lid 104 isclosed.

With rotational assembly 48 secured to drive motor assembly 132, driveshaft 362 is passed down through drive motor assembly 132 and intoimpeller assembly 40 where it couples with impeller 64. Once all of theattachments and couplings are complete and container 18 is filled withthe desired fluid, clamps 238 are closed on fluid lines 232A and 232B(FIG. 6) so as to close off any further communications through thelines. Fluid lines 232A and 232B can then be disconnected from the fluidsource and the gas outlet line after which the entire fluid lines 232Aand 232B can be coiled and placed on top of container 18 within tankassembly 12. Lid 104 is then closed and locked in place using fastener156.

Either before or after closing lid 104, drive motor assembly 132 isactivated to begin mixing fluid within container assembly 16. Thismixing of the fluid is not always required by helps to ensure that allof the fluid is uniformly heated within container 18. Furthermore, themixing helps to ensure that the fluid is homogeneous when it isdispensed for subsequent use. Heated fluid is pumped through the jacketof tank assembly 12 so that fluid within container 18 is heated. Theheating can be started at any stage, i.e., before or after disconnectingfluid line 232A from the fluid source. By having lid 104 closed and allsides of tank assembly 12 heated, along with the fluid in container 18being mixed, the fluid can be uniformly and accurately heated withprecision. The fluid is typically heated to a desired temperature afterwhich that temperature is maintained for desired period of time toachieve desired results.

For example, to inactivate yeast, the fluid within container 18 isheated to a temperature of approximately 60° and maintained at thattemperature for approximately 75 minutes. The temperature and the timefor maintaining the temperature can vary depending on the desiredprocessing. Furthermore, the temperature may be raised or lowered atdifferent stages. Likewise, in contrast to using tank assembly 12 forheating, it is also appreciated that chilled fluid can be passed throughthe jacket of tank assembly 12 for chilling the fluid within containerassembly 16.

To ensure that all of the fluid in container assembly 16 is properlyheated, an electrical heating element 322, as shown in FIG. 5, can bewrapped around the portion of drain line 310 extending between contain18 and clamp 238. Electrical heating element 322 can heat the fluidwithin drain line 310 to the same temperature as the fluid withincontainer 18. This ensure proper heating of the fluid within drain line310. Clamp 238 is not opened until after all of the fluid has beenproperly heated.

Once the fluid within container assembly 16 has been properly processed,the heating can be discontinued. Drain line 310 can then be coupled in asterile manner with a container or further line for draining fluid fromcontainer 18. If desired, mixing of the fluid within container 18 maycontinue to ensure that the fluid is homogeneous as it is dispensed.

When the processing is complete, drive shaft 362 is removed androtational assembly 48 is separated from drive motor assembly 132.Container assembly 16 can then be separated from tank assembly 12 anddisposed of. A second container assembly 16 can then be couple with tankassembly 12 in the same manner as discussed above and the processrepeated.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

What is claimed is:
 1. A fluid heating system comprising: a tankassembly having an interior surface bounding a chamber, the tankassembly comprising: a sidewall encircling the chamber and extendingbetween a first end and an opposing second end, the first end boundingan opening to the chamber; a lid movable between a first positionwherein the opening to the chamber is exposed and a second positionwherein the lid is disposed over the opening; and a floor disposed atthe second end of the sidewall; a collapsible bag removably disposedwithin the chamber of the tank assembly, the collapsible bag bounding acompartment adapted to hold a fluid; means for controlling thetemperature of the fluid within the collapsible bag when the collapsiblebag is positioned within chamber of the tank assembly; an impellerdisposed within the compartment of the collapsible bag; an elongateddrive shaft removably coupled with the impeller such that rotation ofthe drive shaft facilitates rotation of the impeller within thecompartment of the collapsible bag; and a drive motor assembly coupledwith the drive shaft, the drive motor assembly being adapted to rotatethe drive shaft when the lid is in the first position or the secondposition.
 2. The fluid heating system as recited in claim 1, furthercomprising an opening extending through the sidewall of the tankassembly, the drive motor assembly being disposed within the opening soas to communicate with the chamber of the tank assembly.
 3. The fluidheating system as recited in claim 1, further comprising a rotationalassembly mounted to the collapsible bag, the rotational assemblycomprising: a casing secured to the collapsible bag; and a hub rotatablymounted to the casing, the hub having a passageway extendingtherethrough, the drive shaft extending through the passageway of thehub.
 4. The fluid heating system as recited in claim 3, furthercomprising an elongated tubular connector having a first end and anopposing second end, the first end of the connector being connected tothe hub and the second end of the connector being secured to theimpeller, the drive shaft being disposed within the tubular connector.5. The fluid heating system as recited in claim 1, wherein the means forcontrolling the temperature of the fluid comprise a fluid channeldisposed within the lid and the sidewall of the tank assembly.
 6. Thefluid heating system as recited in claim 5, further comprising: a boilerfor heating fluid; and a pump for pumping the heated fluid from theboiler through the fluid channel within the lid and sidewall of the tankassembly.
 7. The fluid heating system as recited in claim 1, furthercomprising: a temperature port assembly coupled to the collapsible bag,the temperature port assembly bounding a cavity that projects into thecompartment of the collapsible bag but is not in fluid communicationwith the compartment; and a temperature probe positioned with the cavityof the temperature port assembly.
 8. The fluid heating system as recitedin claim 7, further comprising a support extending between the tankassembly and the temperature port assembly, the support supporting thetemperature port assembly within the chamber of the tank assembly at adistance from the sidewall.
 9. A fluid heating system comprising: a tankassembly having an interior surface bounding a chamber, the tankassembly comprising: a sidewall encircling the chamber and extendingbetween a first end and an opposing second end, the first end boundingan opening to the chamber; a lid movable between a first positionwherein the opening to the chamber is exposed and a second positionwherein the lid is disposed over the opening; and a floor disposed atthe second end of the sidewall; a collapsible bag removably disposedwithin the chamber of the tank assembly, the collapsible bag bounding acompartment adapted to hold a fluid; a temperature port assembly coupledto the collapsible bag, the temperature port assembly bounding a cavitythat projects into the compartment of the collapsible bag but is not influid communication with the compartment; a temperature probe positionedwith the cavity of the temperature port assembly; and a supportextending between the tank assembly and the temperature port assembly,the support supporting the temperature port assembly within the chamberof the tank assembly at a distance from the sidewall.
 10. The fluidheating system as recited in claim 9, further comprising means forcontrolling the temperature of the fluid within the collapsible bag whenthe collapsible bag is positioned within chamber of the tank assembly.11. The fluid heating system as recited in claim 10, wherein the meansfor controlling the temperature of the fluid comprises: a fluid channeldisposed within the lid and the sidewall of the tank assembly; a boilerfor heating fluid; and a pump for pumping the heated fluid from theboiler through the fluid channel within the lid and sidewall of the tankassembly.
 12. The fluid heating system as recited in claim 9, furthercomprising means for mixing the fluid within the collapsible bag whenthe collapsible bag is disposed within the chamber of the tank assembly.13. The fluid heating system as recited in claim 9, wherein thetemperature port assembly comprises: a port secured to the flexible bag;and a probe adapter secured to the port, the probe adapter comprising: atubular sleeve received over the port; a mounting flange radiallyoutwardly projecting from the sleeve; and a receiver coupled to thesleeve and projecting down through the sleeve, the receiver bounding thecavity of the temperature port assembly.
 14. The fluid heating system asrecited in claim 13, wherein the support comprises: a flange mounted tothe sidewall of the tank assembly and projecting into the chamber; and aretainer disposed at an end of the flange, the probe adapter beingsupported on the retainer.
 15. The fluid heating system as recited inclaim 14, further comprising a clamp removably securing the probeadapter to the retainer.